The present invention relates generally to methods and systems for printing on objects, and, more particularly, to methods and systems for applying images to golf balls, ornaments, and other spherical, semi-spherical, or other objects having curved, non-planar, or non-linear surfaces.
Techniques for applying images to objects having curved, non-planar, or non-linear surfaces are generally limited. One approach has to been to apply a decal to the surface and then spray the object with a clear overcoat finish. The use of decals is somewhat cumbersome. For example, when the spherical objects are golf balls, the decals are typically provided to the golf ball manufacturer by an outside vendor. The decals are relatively expensive and the process of applying the decals to the surfaces of the golf balls is labor-intensive. In addition to being expensive, the use of decals also limits the type of images that may be applied to the objects. Decals are typically made using a silk screening process that cannot provide many types of images, such as images with shading.
Pad printing is another technique for applying images to an object. Examples of pad printing systems are disclosed in U.S. Pat. No. 5,537,921 to Adner et al. and in U.S. Pat. No. 5,806,419 to Adner et al., the disclosures of which are hereby incorporated by reference. Although the pad printing technique eliminates the need for decals, the pad printing technique is also complicated and has its own limitations. In general, pad printing involves forming an image pattern in a printing plate and passing an ink cup over the printing plate so as to fill the pattern in the plate with ink. As the ink cup passes over the printing plate, a blade contacts the plate and wipes off excess ink from the image pattern thereby leaving ink only in the grooves of the pattern. The ink is then transferred to a flexible pad, such as a flexible silicone pad, which is placed in contact with the image plate. The pad is then removed from the plate and then moved into contact with the surface to be printed, such as the surface of a golf ball.
The pad printing technique is limited in the types of images that can be applied to many objects. As discussed above, the pad printing technique involves the use of a printing plate engraved with an image pattern. Thus, when applying images to a golf ball, the pad printing system is limited to the pattern on the plate. To provide a different image on a golf ball, a new plate must be fabricated which has the desired image and this new plate must then be placed in the printing system. The process of exchanging the printing plates requires the system to be turned off, thereby wasting valuable time and money in the production of the golf balls. The printing plates themselves can be fabricated from relatively expensive materials and require some lead-time to engrave the image into the plates. Consequently, before a new image can be applied to the golf ball, the system must wait for the new plate to be fabricated.
The typical pad printing system is also limited in the colors that may be applied to a golf ball. The pad printing systems typically include a number of wells for holding different colors of inks. Thus, the number of colors that may be applied to the golf ball is limited by the number of wells that form part of the printing system.
Another technique for applying images to a golf ball is disclosed in U.S. Pat. No. 5,778,793 to Mello et al., which is hereby incorporated by reference. This technique, as explained in the patent, overcomes some of the disadvantages of conventional pad printing systems and allows for the use of shading or multiple colors on golf balls. This technique involves the use of plates having a photo sensitive coating. The plate with the coating is exposed to an image and to ultra violet light. Portions of the plate that are not part of the image receive the ultra violet light and the coating becomes hardened. After an initial exposure, a screen film is applied over the plate and then the uncured coating is removed, such as in a water bath. Although the technique disclosed in the patent to Mello et al. allows for greater variety of images that may be applied to a golf ball, the printing technique still involves the use of a printing plate or cliche. The technique disclosed in the Mello et al. patent suffers from many of the same disadvantages as other pad printing systems.
U.S. Pat. No. 5,831,641 to Carlson, which is incorporated herein by reference, describes another type of system for printing on objects. This system discloses the use of an ink jet plotter to apply images to a baseball bat. The system also includes a mechanism for holding, positioning, and rotating the bat relative to the ink jet plotter. This type of system advantageously can apply images to objects having non-linear surfaces, such as a baseball bat. As described in this patent, the ink jet plotter moves along a linear axis and applies images to portions of the bat. The bat is divided in three sections with a first section being the end of the bat, the second section being a tapered middle section, and the third section being the handle. The bat is held by a mechanism that pivots the bat so that the bat presents a planar surface to the ink jet plotter. Thus, the system treats each section as a planar surface as it applies the image to the bat.
The system described in the Carlson patent has several shortcomings. For one, the system is limited to three-dimensional objects that have cylindrical sections. The ink jet plotter travels on a linear axis and is therefore only able to apply images to surfaces of the object that are parallel the travel axis of the plotter. Many three dimensional objects, such as balls and ornaments, do not present planar surfaces upon which Carlson""s plotter can apply an image. Thus, the Carlson patent is limited in the types of objects that may be imaged.
The present invention addresses the problems described above by providing methods and systems for printing images on objects having curved, non-planar, or non-linear surfaces. These objects include, but are not limited to, spherical objects such as ornaments, semi-spherical objects such as golf balls, baseballs, or basketballs, and other objects such as eggs, and footballs. A system according to a preferred embodiment of the invention includes a graphics unit that is movable with respect to the object with this graphics unit preferably being an ink jet unit. Graphical information representing the desired graphics on the object is received and is processed into image data. The image data for a desired image to be applied to the object is processed into individual tracks of data to be applied to the object. Each track of data is then transferred to the print head and the position between the print head and the object is controlled so that the track of the desired image is applied to a particular track on the object. In the preferred embodiment, the object is a golf ball and is held and rotated as the print head applies the image to the ball. The print head is also preferably movable with respect to the ball so that the print head is at an optimal position relative to the ball.
The printing systems and methods according to the invention are not limited to a single color. Multiple colors may be applied to an object through the use of multiple graphics units. The invention preferably uses processed color or digital imaging which enables the printing of about 16 million colors. The inks are preferably translucent inks but may comprise any other suitable ink, such as opaque ink or even edible inks. According to one example, the object may be mounted on an indexed table and after printing with one color the object is moved to another print head for the printing of a second color. An intermediate station between the application of two inks may be necessary to allow for the curing or drying of the ink. The objects may be mounted on a table that rotates the object to each successive position or may be mounted on an assembly that moves along a straight path between the print heads. Furthermore, the systems and methods according to the invention are able to maintain the object at a desired position between print heads. Since the position of the object relative to its spin axis is always known, the images from the different colored print heads can be merged to create a desired image having virtually any color.
The invention may be used to apply images to a variety of three-dimensional objects. As discussed above, the invention is not limited to objects having planar or cylindrical surfaces but may be used to apply images to spherical or semi-spherical objects. For instance, the invention preferably has an ink jet plotter that moves about a curved surface and applies desired tracks of images to that curved surface.
According to a further aspect of the invention, a facility for printing images on a plurality of objects includes a hopper or other container for holding the plurality of objects. These objects are then transferred from the hopper to the printing assembly, such as through a chute or other transfer device. The objects are then automatically placed within a manipulator assembly for holding the object and desired images are applied to the objects through one or more print heads. As discussed above, multiple colors may be applied to the object through the use of multiple print heads with each print head applying a different color. After the last color of ink has been applied to the object, the object may be automatically released and placed into a holding bin or sent to a subsequent apparatus for packaging of the objects.
The printing systems and methods according to the invention allow for the application of a greater variety of images. The systems and methods do not rely upon image plates nor do they require any type of cliche. Instead, any image that can be captured with a computer is broken down into its individual colors, its individual tracks, and each track is then applied to the object. Further, the printing systems and methods are not limited to just a portion of the object""s surface but may be applied around the entire perimeter of the object. Because the printing systems and methods do not use any image plate, the image that is applied to the object can be quickly and easily changed.
Accordingly, it is an object of the present invention to provide systems, methods, and assemblies for applying images to objects.
It is another object of the present invention to provide systems, methods, and assemblies for applying images to spherical or semi-spherical objects or objects having curved or non-linear surfaces.
It is a further object of the present invention to provide systems, methods, and assemblies for applying images to objects in which the image can be quickly and easily changed.
It is still a further object of the present invention to provide systems, methods, and assemblies for applying images to objects in multiple colors and in various degrees of resolution.
It is yet another object of the present invention to provide systems, methods, and assemblies for applying images to a plurality of objects.
It is still another object of the present invention to provide systems, methods, and assemblies that do not require image plates or cliches.
Other objects, features, and advantages of the present invention will become apparent with respect to the remainder of this document.